I had all 4 of my house batteries split and crack open last winter while the coach was plugged in. A new one for me. These batteries had been installed less than 2 years ago and were Interstates. I called them and they just gave me a lot of crap. The most likely reason was low fluid level causing freezing.

Re warning lights on Frieghtliner: Don't let them tell you not to worry about this because this happened in my coach within less then a year after I bought it and when Frieghtliner checked it out, they even told me it was OK.
At less than 16k miles the over heat light came on then the coach shut down. I was out on an interstate in Mass at the time. I got out to see antifreeze running all over the place and thought I had blown a hose. I called Cummins road service who was there in less than one hour. He crawled under the coach, and then he had a big grin on his face when he told me the block was cracked! Luckily I had a road service that towed the unit back to Metroliner in Ct where they replaced the block. The stink to all this is that the Cummins tec told me they were aware of this problem but had not sent out a recall.
So BEWARE and pursue the problem with Frieghtliner. That was on the 275hp IB engine.